The role of alkaloids in cigarette smoke was investigated in the cumulus expansion of oocyte-cumulus complexes (OCC) isolated from large antral porcine follicles. Suppression of the cumulus expansion stimulated by FSH was observed in the presence of different concentration of cadmium, anabasine and nicotine but not its metabolite cotinine. There were comparable inhibitory effects of cadmium and nicotine on the synthesis and accumulation of hyaluronic acid in the cell/matrix compartment of OCC. The inhibitory effect of tested compounds on the cumulus expansion was accompanied by decreased progesterone synthesis by cumulus cells during 42 h incubation of OCC with FSH. The results suggest that cigarette smoking may affect intrafollicular processes, which are responsible for normal ovulation and fertilization., S. Vršanská, E. Nagyová, A. Mlynarčíková, M. Ficková, J. Kolena., and Obsahuje bibliografii
The aim of this study was to investigate the concentrations of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), leptin, tumor necrosis factor-α, interleukin (IL)-1β and IL-6, in cycles with a premature rise of serum progesterone. 25 intracytoplasmic sperm injection (ICSI) cycles with (Group 1) and 25 ICSI cycles without a premature progesterone elevation (Group 2) were included. The cut-off value of serum progesterone on the day of human chorionic gonadotropin (hCG) administration was 0.9 ng/ml. The indication for ICSI was male factor infertility exclusively. On the day of hCG injection, serum IL-6, VEGF and bFGF were significantly higher in Group 1 (7.7±24.5 pg/ml, 290.2±161.4 pg/ml and 15.7±8.2 ng/ml respectively) than in Group 2 (1.7±0.7 pg/ml, 175.2±92.1 pg/ml, and 9±1.6 ng/ml respectively). On the day of follicular puncture, serum cytokine concentrations were similar in the two groups. IL-6 intrafollicular concentrations were higher in Group 1 (14.7±20.7 pg/ml) than in Group 2 (9±9.3 pg/ml, p=0.031). There were no differences regarding the ICSI outcome. Patients with serum progesterone above 0.9 ng/ml, have elevated serum concentrations of IL-6, VEGF, and bFGF, as well as elevated intrafollicular concentrations of IL-6. The outcome of ICSI cycles is not associated with premature elevation of progesterone when the cut-off value is set at 0.9 ng/ml., N. Nikolettos, B. Asimakopoulos, F. Köster, B. Schöpper, Ch. Schulz, G. S. Caglar, A. Efthimiadou, O. Pagonopoulou, K. Diedrich, S. Al-Hasani., and Obsahuje bibliografii a bibliografické odkazy
a1_The wide chemical diversity of estrogenic compounds precludes an accurate prediction of estrogenic activity on the basis of chemical structure or radioimmunological assay and thus requires that the potency of these compounds is defined by bioassay. The mammary duct growth response in intact prepubertal and adult gonadectomized female and male mice of the C3H/Di strain was used to assess the estrogenicity of synthetic compounds or their derivatives. The vehicle for tested compounds should be free of estrogenic and other hormonal effects. Olive oil or sunflower oil exerted estrogenic activities and were thus unsuitable as vehicles for the tested compounds. The absence of estrogenic activity, high solubility of different steroid hormones, and the low incidence of the inflammatory reactions at the injection site were achieved by using a vehicle containing benzyl alcohol, benzyl benzoate, butylhydroxyanisole, butylhydroxytoluene, ethyl oleate and ethanol. The bioassay was primarily designed to examine the effect of tested compounds on mammogenesis. The duration of hormone treatment was chosen to be long enough for induction of duct growth but too short to induce lobuloalveolar differentiation. Females were treated for 10 days, males for 15 days. The proportional volume occupied by mammary epithelial structures was estimated by the modified Chalkley's technique. The mean coefficient of variation of quantitative evaluation of 10 different mammary glands obtained by two operators varied between 3.2 and 17.4 %. The mean coefficient of variation of quintuplicate determinations of each mammary gland by one operator was 10.1 %, and 11.1 % by the other. The correlation coefficient between results of two operators was 0.994. Estrogens are primarily defined by their ability to increase the mitotic activity of female secondary sex organs., a2_However, our results have shown that progesterone alone, if administered in a high dose, stimulates mammary growth in both intact prepubertal and OV-X female mice similarly as the synthetic progestatial steroid norethindrone with inherent estrogenic properties. In contrast, progesterone alone had no effect, in young intact or adult castrated males, but norethindrone did stimulate mammary growth. These results demonstrated that the mammary gland of males is a suitable model for estrogen screening., J. Škarda., and Obsahuje bibliografii
The effects of 8-days treatment with 17α-estradiol (33.3 μg/kg) and progesterone (1.7 mg/kg) on plasma lipids and fatty acid composition of plasma phospholipids were examined in intact (INT) and bilaterally common carotid arteries occluded (BCO) male Wistar rats. Significant decrease of triglyceride level was found in BCO rats after the estradiol treatment. Both hormones elevated proportion of 18:1n-7 fatty acid in INT, but they failed to have such an effect in BCO. Estradiol increased 22:5n-3 and total n-3 polyunsaturated fatty acids (PUFA) in intact, and decreased 18:2n-6 in BCO rats. Significantly lower level of total n-3 was found in progesterone-treated than in estradiol-treated BCO rats. Given that n-3 PUFA have many beneficial effects on cell and tissue function, while n-6 PUFA have mostly the opposite effects, estradiol, rather than progesterone, was seen to improve plasma lipids and phospholipids FA profiles in INT and BCO animals. Estradiol significantly elevated the estimated activity of Δ9-desaturases and progesterone of Δ5-desaturase in BCO group, with no effects in INT rats., S. Petrović, M. Takić, A. Arsić, V. Vučić, D. Drakulić, M. Milošević, M. Glibetić., and Obsahuje bibliografii
The activity of mitochondrial superoxide dismutase (MnSOD) and cytosol superoxide dismutase (CuZnSOD) was measured in corresponding subcellular fractions prepared from the thymi of intact and chronically gonadectomized (GX) rats of both sexes, as well as of GX male and female rats injected subcutaneously with a single dose of 5 mg estradiol benzoate (EB) and/or 2 mg progesterone (P). Animals were sacrificed 2 h or 24 h following hormone treatment. In the females, the activity of MnSOD in the thymus was stable during the estrous cycle and did not change after ovariectomy. Treatment of GX females with estradiol benzoate resulted 2 h later in a significant elevation of MnSOD activity, whereas 24 h later the activity returned back to control values. On the other hand, treatment of GX females with progesterone had no effect on the MnSOD activity. However, combined hormone treatment, in which EB injection preceded progesterone injection by one hour, enhanced the effect on MnSOD activity similar to that of estradiol benzoate alone. The activity of CuZnSOD in cycling rats was increased in proestrus, whereas removal of the ovaries kept the values at low diestrus and estrus levels. Contrary to MnSOD, CuZnSOD activity did not change after EB treatment of GX females, while progesterone increased the enzyme activity at 2 h and 24 h after hormone treatment. However, combined EB+P treatment proved to be ineffective. In the males, neither MnSOD nor CuZnSOD activity was affected by the removal of testes or by progesterone treatment of GX animals. Only EB injection to GX rats significantly increased CuZnSOD activity 24 h later., J. Kasapović, S.B. Pajović, S. Pejić, J.V. Martinović., and Obsahuje bibliografii
t would be desirable to expand the existing general knowledge concerning direct action of metals on the ovary. Nevertheless, the results of testing of iron compound on porcine ovarian cells should be interpreted carefully because iron is an essential element which could also induce changes in cellular processes. The aim of this in vitro study was 1) to examine dose-dependent effects of iron on the secretory activity of porcine ovarian granulosa cells, and 2) to outline the potential intracellular mediators mediating these effects. Specifically, we evaluated the effect of iron sulphate on the release of insulin-like growth factor I (IGF-I) and progesterone, as well as the expression of markers of proliferation (cyclin B1) and apoptosis (caspase-3) in porcine ovarian granulosa cells. Concentrations of IGF-I and progesterone were determined by RIA, cyclin B1 and caspase-3 expression by immunocytochemistry (ICC). Our results show a significantly decreased IGF-I secretion by ovarian granulosa cells after iron sulphate addition at the doses 0.5 and 1.0 mg/ml. The iron sulphate additions at do ses 0.17 and 1.0 mg/ml had no effect on progesterone secretion. In contrast, iron sulphate addition at doses 0.17-1.0 mg/ml resulted in stimulation of cyclin B1 and caspase-3 expression. In conclusion, the present results indicate a direct effect of iron on 1) secretion of growth factor IGF-I but not steroid hormone progesterone, 2) expression of markers of proliferation (cyclin B1), or 3) apoptosis (caspase-3) of porcine ovarian granulosa cells. These results support an idea that iron could play a regulatory role in porcine ovarian function: hormone release, prolif eration and apoptosis., A. Kolesarova ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
The aim of this in vitro study was to examine the secretion activity (progesterone, 17β-estradiol and insulin-like growth factor-I) of rat ovarian fragments after molybdenum (Mo) addition. Rat ovarian fragments were incubated with ammonium molybdate (NH4)6Mo7O24.4H2O at the doses 90, 170, 330 and 500 μg.ml-1 for 24 h and compared with control group without Mo addition. Release of progesterone (P4), estradiol (17β-estradiol) and insulin-like growth factor I (IGF-I) by ovarian fragments was assessed by radioimmunoassay (RIA). Data show that P4 release by ovarian fragments was not affected by (NH4)6.Mo7O24.4H2O addition at all the doses used (90-500 μg.ml-1). However, addition of ammonium molybdate was found to cause a significant (P<0.05) dose-dependent decrease (at the doses 90, 170 and 500 μg.ml-1) in release of 17β-estradiol by ovarian fragments in comparison to control. Also, addition of ammonium molybdate significantly (P<0.05) inhibited IGF-I release at all the doses (90-500 μg.ml-1) used in the study. Results suggest ammonium molybdate induced inhibition in the release of growth factor IGF-I and its dosedependent effect on secretion of steroid hormone 17β-estradiol but not progesterone. These data contribute to new insights regarding the mechanism of action of Mo on rat ovarian functions., S. Roychoudhury, L. Detvanova, A. V. Sirotkin, R. Toman, A. Kolesarova., and Obsahuje bibliografii
a1_Progesterone and estradiol are the foremost steroid hormones in human pregnancy. However, the origin of maternal progesterone has still not been satisfactorily explained, despite the generally accepted opinion that maternal LDL-cholesterol is a single substrate for placental synthesis of maternal progesterone. The question remains why the levels of progesterone are substantially higher in fetal as opposed to maternal blood. Hence, the role of the fetal zone of fetal adrenal (FZFA) in the synthesis of progesterone precursors was addressed. The FZFA may be directly regulated by placental CRH inducing an excessive production of sulfated 3β-hydroxy-5-ene steroids such as sulfates of dehydroepiandrosterone (DHEAS) and pregnenolone (PregS). Due to their excellent solubility in plasma these conjugates are easily transported in excessive amounts to the placenta for further conversion to the sex hormones. While the significance of C19 3β-hydroxy-5-ene steroid sulfates originating in FZFA for placental estrogen formation is mostly recognized, the question “Which maternal and/or fetal functions may be served by excessive production of PregS in the FZFA?“ - still remains open. Our hypothesis is that, besides the necessity to synthesize de novo all the maternal progesterone from cholesterol, it may be more convenient to utilize the fetal PregS. The activities of sulfatase and 3β-hydroxysteroid dehydrogenase (3β-HSD) are substantially higher than the activity of cytochrome P450scc, which is rate-limiting for the placental progesterone synthesis from LDL-cholesterol. However, as in the case of progesterone synthesis from maternal LDL-cholesterol, the relative independence of progesterone levels on FZFA activity may be a consequence of substrate saturation of enzymes converting PregS to progesterone., a2_Some of the literature along with our current data (showing no correlation between fetal and maternal progesterone but significant partial correlations between fetal and maternal 20α-dihydroprogesterone (Prog20α) and between Prog20α and progesterone within the maternal blood) indicate that the localization of individual types of 17β-hydroxysteroid dehydrogenase is responsible for a higher proportion of estrone and progesterone in the fetus, but also a higher proportion of estradiol and Prog20α in maternal blood. Type 2 17β-hydroxysteroid dehydrogenase (17HSD2), which oxidizes estradiol to estrone and Prog20α to progesterone, is highly expressed in placental endothelial cells lining the fetal compartment. Alternatively, syncytium, which is directly in contact with maternal blood, produces high amounts of estradiol and Prog20α due to the effects of type 1, 5 and 7 17β-hydroxysteroid dehydrogenases (17HSD1, 17HSD5, and 17HSD7, respectively). The proposed mechanisms may serve the following functions: 1) providing substances which may influence the placental production of progesterone and synthesis of neuroprotective steroids in the fetus; and 2) creating hormonal milieu enabling control of the onset of labor., M. Hill ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
In the present in vitro experiments we examined FSH- and ghrelin-induced changes in ovarian hormone secretion by transgenic rabbits. Fragments of ovaries isolated from adult transgenic (carrying mammary gland-specific mWAP-hFVIII gene) and non-transgenic rabbits from the same litter were cultured with and without FSH or ghrelin (both at 0, 1, 10 or 100 ng/ml medium). The secretion of progesterone (P4), estradiol (E2) and insulin-like growth factor I (IGF-I) was assessed by RIA. It was observed that ovaries isolated from transgenic rabbits secreted much less P4, E2 and IGF-I than the ovaries of non-transgenic animals. In control animals FSH reduced E2 (at doses 1-100 ng/ml medium) and IGF-I (at 1-100 ng/ml), but not P4 secretion, whereas ghrelin promoted P4 (at 1 ng/ml) and IGF-I (at 100 ng/ml), but not E2 output. In transgenic animals, the effects were reversed: FSH had a stimulatory effect on E2 (at 100 ng/ml) and ghrelin had an inhibitory effect on P4 (at 10 ng/ml). No differences in the pattern of influence of FSH on P4 and IGF-I and of ghrelin on E2 and IGF-I were found between control and transgenic animals. The present observations suggest that 1) both FSH and ghrelin are involved in rabbit ovarian hormone secretion, 2) transgenesis in rabbits is associated with a reduction in ovarian secretory activity, and 3) transgenesis can affect the response of ovarian cells to hormonal regulators., A. V. Sirotkin, P. Chrenek, K. Darlak, F. Valenzuela, Ž. Kuklová., and Obsahuje bibliografii a bibliografické odkazy
The brain is widely responsive to gonadal hormones. The functional significance of ovarian hormones in the brain is evident from biochemical studies indicating that estradiol or progesterone treatment of testectomized rats produces changes of antioxidant enzyme activities. The effect of estradiol benzoate (EB) and progesterone (P) in the control of antioxidant (AO) enzyme activities was studied in the brain of adult male Wistar rats. The activities of catalase (CAT), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST) and glutathione reductase (GR) were measured in appropriate subcellular fractions, prepared from brains of animals belonging to various experimental groups. These groups were designed with the intention to follow changes in enzyme activities 2 h or 24 h after systemic administration of 5 g EB or 2 mg P to testectomized (TX) animals. The obtained results show that both EB and P increase CAT activity, whereas EB decreases GSH-Px, GST and GR activities. These findings clearly show the modulatory role of EB and P in the control of enzymes responsible for the protection of rat nerve cells against oxidative damage caused by free oxygen radicals., S. B. Pajović, Z. S. Saičić, M. B. Spasić, V. M. Petrović., and Obsahuje bibliografii